Switch mechanism



A. A. GAZDA.

SWITCH MECHANISM, APPLICATION FILED NOV. I9, 1917.

Patented Sep 28, 1920.

ham/alibn,

INVENTOR Ado/M A. Gazda WITNESSES: 45 mmg W a Md.

ATTORNEY ADOHLPH A. GAZDA, or WILKInsBUne, rmv

ELECTRIC & MAN UFAGTURIN G CGMPAN NSYLVANIA, ASSIGNOR TO T OFFICE.

WESTINGHOUSE Y, A CORPQRATION OF PENNSYLVANIA.

SWITCH MECHANISM.

Application filed November 19, 1917.

1' 0 all whom it may concern:

it imown that 1, ADOLPH A. GAZDA, a citizen of the United States, and a resident of ll ilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Switch Mechanisms, 'of which the following is a specification. p

invention relates to switch mechanisms and particularly to. switch mechanisms forgoverning the operation of electric motors.

One object of my invention is to provide a switch mechanism of the above-indicated character that shall be simple, rugged, and relatively inexpensive in construction and reliable and effective in operation.

In acceierating an eiectric motor, and particularly in acceierating a shunt-wound direct-current motor, it is essential to provide a resistor in the armature circuit which shall be short-circuited, either manually or automatically, when the motor is operating at normal speed. In many cases, a number of resistors, which are successively short-circuited'in accordance with the current flowing through the motor, are initially inserted in series with the motor armature. hen a motor-control system is provided with a number of resistors, as in the example last mentioned, and it is desired to automatically short circuitthe same. it is customary to provide a set of switches, separate from the resistor-short-circuiting switches, that are operated in'a predetermined order inac cordance with the current flowing through thefmotor for effecting the operation of the resistor-short-circuiting switches. The auxiliary accelerating switches are somewhat expensive in construction and add somewhat more of apparatus to the control system.

In a motorcontrol system provided with switch mechanisms that are constructed in accordance with my invention, the resistorshort-circuiting switches are provided with auxiliary switches which are controlled by the. resistor switches in a manner to automatically effect operation of the resistor switches in accordance with the current flowing through the motor. Each of the resistor switches is provided with an auxiliary switch which is held in an open position by means of a spring mechanism. An armature'is associated with the energizing coil of 'thevresistorswitch in a manner to release Specification of Letters Patent.

Patented Sept. Serial No. 202,701.

the spring mechanism when the resistor switch is operated. sistor switch is operated and mechanism is released, which is associated with However, when the re the spring the blowout coil the resistor switch is energized and serves to hold the auxiliary switch in an open position until the current flowing through th motor has be en reduced sufficiently to permit the closing of the next resistor-short-circuiting switch. I

in the accompanying drawing Figure l l, and Fig. 3 is a plan view of mechanism illustrated in Figs.

i is a diagrammatic view of the switch l and 2. Fig. a plurality of int rconnected switch mechanisms.

Referring to the accompanying drawing,

a switch mechanism 1, embodying a main switch 2 and ed upon an insulating support i. switch 2 embodies a pair of relat an auxiliary switch 3,

is mount- The main ively movable contact terminals 5 and 6, an energizing coil 7, and a blowout coil 8. member 5 is pivotally The contact mounted on an armature 9 which is adapted to be attracted by the energizing coil 7. which is pivotally mounted on a able frame 10, is provided with a ll'for engaging a lug 12 to The armature 9,

magnetiz- PIOJBCUOH prepare 311 311K- iliary magnetic circuit for a purpose to be set forth hereinafter.

The auxiliary switch 3 embodies an arm 13, which is bracket 14-, to the arm blowout coil pivotally supported upon a an armature 15, which is joined and is associated l with the S, and a contact member 16 which is adapted to bridge contact terminals l7 and 18 is operated. The contact termin 18 are connected in circuit with the coil 7 the next succeeding switch 2, as is matically represented at Fig. 4;.

A spring mechanism 19, which position to a spring 20,

maintaining the auxiliary when the auxiliary switch 3 als l7 and of diagramacts in 0pis provided for switch 3 in an openposition when the main switch 2 is deenergized. The spring mechanism 19 embodles a rod 21 which passes through the support i and the arm 13 of th and is provided with enlarged he e switch 3 ads 22 and 23 near the ends thereof. The head 23 of the rod 21 is adapted to engage t he arm 13,

i insulating support 5 and a coil spring 2 l is disposed around the,

the head 22 and the in a manner to maintain the auxiliary switch 3 in an open posilQQl. 21, intermediate armature 25 is attracted coil 7 When it by the energizing isdesired to operate the switch mechanism 1, a circuit is Completed through I for attracting the arthe energizing coil 7 V the magnetic circuit mature 9; As soonas V for the energizing coil 7 is completed by the armature 9, sufhcient flux is produced for attracting the armature 25 in order to coin-' press the spring 2% and permit the releasing of the spring mechanism 19. However,

when the main switch 2 is closed and the spring mechanism 19 is released by the armature 25, the blowout coil'8 is energized so as to attract thearmature 15 of the, auxiliary switch 3 and prevent the closing of the aux- .iliary switch at this time.

The action of the blowout coil 8 ci -the armature 15 is 0pposed by'the spring 20 and, when the motor current flowing through the. blowout coil 8 issufii'ciently reduced, the auxiliary. switch 3 is closed by-the spring 20 for. energizing the next resistor-short-circuiting sw tch. In the system illustrated n Fig. l, an electric motor 30 has armature'Sl and a series field-magnet winding 32. 'The motor circuit and a starting resistor 33 are controlled by series or switches of the type illustrated in Figs. '1',

'iliary switch 2 and 3, similar numerals being employed to designate corresponding parts. It will be readily understood that the aux- 3 is omitted from' the last switch to close. A push-button switch 34:,

controls a circuit comprising theact'uating ingcoil, a

The various switches and circuits ofthc 5 tion. l a I system are restored to their initial positions An armature 25, which is pivotally mouftupon the opening of r the push-button ed upon the insulating support 4:, is disposedswitch 34. I Y in a position to be attracted by the main v Modificationsin the apparatus and'ar-' energizing coil 7 when thesame is energized rangement and: location or parts may be r 10 for operating the main switch 2. When the made within the spirit and scope or my 75. armature 9 is attracted by the coil 7, a 'maginvention and such modifications, are innetic circuit is prepared for the armature tended to be covered by the appended claims. 25 that includes the armatureprojection 11, I claim as my invention: the lug'l2, an d a'lug 26 which projects from '1. In a switch mechanism, the combina- 15 the coil or the electromagnet. The armation with a main switch having an enerture 25 is-sof disposed in. relation to the gizing and a'blowout coil, and an auxiliary spring device 19 that one end thereof is switchbiased to its open position, of means adapted to engage the head 22 of the rod controlled by said energizing coilzfor effect- 21 in order to compress the spring 24' and ing the clcsing'or saidauxiliary Slv'li3l1*,-&l1(l 20 release the auxiliary switch 3 whenever the meanscontrolled by the blowout coilfor permitting the closing. of the auxiliary switch under predetermined conditions.

2. In a switchmechanism, the combination with a main switch having an energizinain switch, and an auxiliary switch coir trolled bysaidenergizing coil, ofa spring. 7

for holding the au liary switch in an open position, and means wherebythe operation of the auxiliary switch is controlled by said blowout coil. v

3. In a switch mechanism,the combination with a main switch having an energiz- 111g and a blowout coil, and an auxiliary switch having a spring mechanism for main taining the same in an open position,.oi means controlled by said energizing coil for releasing the spring mechanism, and means controlledby the blowout coil for permit-' ting. the closure of the'auxiliary switch under predetermined conditions.

41 In a switch mechanism,: the combination with a main switchand an auxiliary switch ELSSOClEltGCl with the'main switch,;.of

means controlled in accordance with the position of said main switch for maintaining the auxiliary switch in its open position,

and ablowout coil associated with themain switch for permitting the operation ofthe,

auxiliary switchunder predetermined conclitions. 1 r

5. In a switch mechanism,the combination'with a mainswitch havinga blowout coil associated therewith, of an auxiliary blowout coil in circuit with the coils? of the main switches and the auxilswitch normally maintained in its open poiary switches. V sition, common means for effecting the Upon the" actuation of the push-button closure of said main switch and said auxswitch 3%, the first switch of the series opiliary switch, and means controlled by said I I eratesin the manner described above in conblowout coil for preventing the closing of motor circuit has fallen to a predetermined value. The coil 7 of the succeeding switch 60 said auxiliaryswitch conditions. r r

6'. In a switch mechanism, the combina tion with a main switch having a blowout coil associated therewith, and an" auxiliary under predetermined "12 5 switch, of means for biasingsaid auxiliary .1-30

switch to its 0 en position, and means jointly controller by the main switch and the blowout coil for permitting the operation of the auxiliary switch under predetermined conditions.

7. In a switch mechanism, the combination with a main switch having an energizing coil, of an auxiliary switch, a spring mechanism for maintaining the auxiliary switch in its open position, means for releasing the spring mechanism when the main coil is energized, and a blowout coil associated with the main switch for releasing the auxiliary switch under predetermined conditions.

8. In a switch mechanism, the combination with a main switch having an energizing and a blowout coil, an auxlliary switch, and a spring mechanism for maintainin the auxiliary switch in an open position, 0% an armature controlled by said energizing coil for releasing the spring mechanism. when the main switch is operated, and means controlled by the blowout coil for holding the auxiliary switch in its open position for a predetermined length of time after the'same is released by the spring mechanism.

v 9. In a switch mechanism, the combination with a main switch having an energizing and a blowout coil, an auxiliary switch, and a spring mechanism for holding the auxiliary switch in its open position, of an armature controlled by said energizing coil for releasing the spring mechanism when .7

the main switch is operated, and means comprising an armature associated with the auxiliary switch and controlled by the blowout coil for holding the auxiliary switch in its open position for a predetermined period of time after the main switch has been operated.

10. In a switch mechanism, the combination with a main coil, a main switch operated by said coil, a blowout coil associated with said main switch, and an auxiliary switch controlled by said blowout coil and maintained in its open position thereby under predetermined conditions, of a spring mechanism for maintaining said auxiliary switch in its open position when the main coil is deenergized, and an armature associated with the main coil for releasing the spring mechanism when the main coil is energized.

In testimony whereof I have hereunto subscribed my name this 30th day of Oct., 1917.

ADOLPH A. GAZDA. 

